<meta charset="utf-8">
(#) Monochrome icon is not defined

!!! WARNING: Monochrome icon is not defined
   This is a warning.

Id
:   `MonochromeLauncherIcon`
Summary
:   Monochrome icon is not defined
Severity
:   Warning
Category
:   Usability: Icons
Platform
:   Android
Vendor
:   Android Open Source Project
Feedback
:   https://issuetracker.google.com/issues/new?component=192708
Since
:   7.4.0 (January 2023)
Affects
:   Resource files
Editing
:   This check runs on the fly in the IDE editor
Implementation
:   [Source Code](https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:lint/libs/lint-checks/src/main/java/com/android/tools/lint/checks/MonochromeLauncherIconDetector.kt)
Tests
:   [Source Code](https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:lint/libs/lint-tests/src/test/java/com/android/tools/lint/checks/MonochromeLauncherIconDetectorTest.kt)

If `android:roundIcon` and `android:icon` are both in your manifest, you
must either remove the reference to `android:roundIcon` if it is not
needed; or, supply the monochrome icon in the drawable defined by the
`android:roundIcon` and `android:icon` attribute.

For example, if `android:roundIcon` and `android:icon` are both in the
manifest, a launcher might choose to use `android:roundIcon` over
`android:icon` to display the adaptive app icon. Therefore, your themed
application iconwill not show if your monochrome attribute is not also
specified in `android:roundIcon`.

(##) Example

Here is an example of lint warnings produced by this check:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~text
res/drawable-ldpi/ic_icon.xml:2:Warning: The application adaptive icon
is missing a monochrome tag [MonochromeLauncherIcon]
    &lt;adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android"&gt;
    ^
res/drawable-ldpi/ic_round_icon.xml:2:Warning: The application adaptive
roundIcon is missing a monochrome tag [MonochromeLauncherIcon]
    &lt;adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android"&gt;
    ^
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Here are the relevant source files:

`res/drawable-ldpi/ic_icon.xml`:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~xml linenumbers
&lt;adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android"&gt;
    &lt;background android:drawable="@drawable/ic_launcher_background" /&gt;
    &lt;foreground android:drawable="@drawable/ic_launcher_foreground" /&gt;
&lt;/adaptive-icon&gt;
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

`res/drawable-ldpi/ic_round_icon.xml`:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~xml linenumbers
&lt;adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android"&gt;
    &lt;background android:drawable="@drawable/ic_launcher_background" /&gt;
    &lt;foreground android:drawable="@drawable/ic_launcher_foreground" /&gt;
&lt;/adaptive-icon&gt;
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

`src/AndroidManifest.xml`:
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~xml linenumbers
&lt;manifest xmlns:android="http://schemas.android.com/apk/res/android" package="test.pkg"&gt;
    &lt;application
        android:icon="@drawable/ic_icon"
        android:roundIcon="@drawable/ic_round_icon"
        android:label="@string/app_name" &gt;
    &lt;/application&gt;
&lt;/manifest&gt;
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

You can also visit the
[source code](https://cs.android.com/android-studio/platform/tools/base/+/mirror-goog-studio-main:lint/libs/lint-tests/src/test/java/com/android/tools/lint/checks/MonochromeLauncherIconDetectorTest.kt)
for the unit tests for this check to see additional scenarios.

(##) Suppressing

You can suppress false positives using one of the following mechanisms:

* Adding the suppression attribute
  `tools:ignore="MonochromeLauncherIcon"` on the problematic XML
  element (or one of its enclosing elements). You may also need to add
  the following namespace declaration on the root element in the XML
  file if it's not already there:
  `xmlns:tools="http://schemas.android.com/tools"`.

  ```xml
  &lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;adaptive-icon xmlns:tools="http://schemas.android.com/tools"
      tools:ignore="MonochromeLauncherIcon" ...&gt;
    ...
  &lt;/adaptive-icon&gt;
  ```

* Using a special `lint.xml` file in the source tree which turns off
  the check in that folder and any sub folder. A simple file might look
  like this:
  ```xml
  &lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;lint&gt;
      &lt;issue id="MonochromeLauncherIcon" severity="ignore" /&gt;
  &lt;/lint&gt;
  ```
  Instead of `ignore` you can also change the severity here, for
  example from `error` to `warning`. You can find additional
  documentation on how to filter issues by path, regular expression and
  so on
  [here](https://googlesamples.github.io/android-custom-lint-rules/usage/lintxml.md.html).

* In Gradle projects, using the DSL syntax to configure lint. For
  example, you can use something like
  ```gradle
  lintOptions {
      disable 'MonochromeLauncherIcon'
  }
  ```
  In Android projects this should be nested inside an `android { }`
  block.

* For manual invocations of `lint`, using the `--ignore` flag:
  ```
  $ lint --ignore MonochromeLauncherIcon ...`
  ```

* Last, but not least, using baselines, as discussed
  [here](https://googlesamples.github.io/android-custom-lint-rules/usage/baselines.md.html).

<!-- Markdeep: --><style class="fallback">body{visibility:hidden;white-space:pre;font-family:monospace}</style><script src="markdeep.min.js" charset="utf-8"></script><script src="https://morgan3d.github.io/markdeep/latest/markdeep.min.js" charset="utf-8"></script><script>window.alreadyProcessedMarkdeep||(document.body.style.visibility="visible")</script>